Debris at the site where a Russian aircraft crashed in Egypt's Sinai Peninsula.

Investigators who pinpointed the exact location of a bomb that brought down a Russian jet said it was planted under the seat of a 15-year-old girl.

The blast over Egypt’s Sinai Peninsula killed all 224 people on board, but no one got it worse than Maria Ivleva, a 15-year-old girl who was traveling with her mother when a bomb ripped apart the plane 23 minutes after leaving Sharm el-Sheikh — a resort that 3 million Russians visit every year — en-route to St Petersburg.